Meaty Tire Thread

[Jive Turkey]

Because i have no idea where my original thread went i figured i start a thread
for ALL BRZ/FRS's that run meaty tire size. anything 255+ would be considered meaty for these purposes, everything else is just "normal" tire size.

just a few things that get asked ALL the time in here:

1) Most of us run a coilover, you really won't fit a 9.5 wheel up front with stock struts and will have minimal clearance with a 245 tire on a 9 inch wide rim with a 40-ish offset.

2) not all suspensions are created equal and not all cars are created equal. if something works on someones car, that doesn't mean it will be identical on yours, generally its true but not always applicable.

3) LCA are needed to adjust rear camber unless you don't care to correct it, you may also need toe arms or more toe adjustment via a bushing depending on your vehicle and LCA setup.

4) rolling and slightly pulling your fenders will give you more clearance than you think, you will always rub on the rear bumper tab unless you trim it first.

please post up you modifications, any fitment tips, and obviously
feel free to use this is a photo dump for others to get ideas. if i need to edit something in the OP just lmk.


and now here is what i went through with my BRZ.

brought to you by @AZP Installs give them a shout
if you need anything, ESPECIALLY alignments, suspension work and track prep.


wheel/tires combo's i've fitted.

18x9.5 +40 Rays Gramlights 57xtreme w/ 265/35 RE-11 tire

18x9.5 +40 Rays Gramlights 57getter w/ 265/35 MPSS tire


Current suspension:
RCE t2 coilover
Group-n top hats front
GR STi rear tophats
SPC camber bolt
SPC rear control arms
Whiteline adjustable toe arms

perviously on AST 4150 and KW V3 and in pictures with xtreme's)

PARTS I DO NO RECOMMEND:
CUSCO rear LCA (PITA to adjust, if you don't do your own alignment then disregard and pay in labor)
WHITELINE COM C tophats (bearing failed 3 times)

YOU WILL RUB at first. its the plastic part of the rear bumper,
its not a big deal and will rub itself out of you can dremel it. (the corner to the bumper inside the fender)

Second I had an issue with my passenger fender, it rubbed on the part closest to the sidemarkers.
if you feel the fender there, it flares out towards the side marker, you want to roll that part in
to avoid any issues in the future or else you risk chipping the paint or gashing the tire....i luckily caught it early.

Third, and probaby most important. once we let the KW's settle we had to take camber out.
it settled to around -3.5' in the rear at the heigh i'm at. i did not want to run that much at
all, nor do i need that much for clearance issues. once it settle i fixed the camber with the
control arms however the STOCK toe arms did not cut it with the Cusco arms..so i upgraded to whitelines

My alignment specs are as follows:

camber F/R= -1.8/1.6 (-2.7 f/-1.8 rear for track)
front toe out= .08
Rear toe in= .08

car drives like a dream.

many dont seem to understand the basic gist of suspension geometry, how things work, how grip and stability is affected so here is a brief write up to explain that

so camber...basically in order to maximize cornering force from your tires, the tire must be square on the road during a corner to achieve max grip. If your car had zero camber (all tires square to the road when driving straight), as soon as you turn, the body will roll to the outside, and the outer tires will roll only on the outsides of the tires. Thats why if you ever drove a car with stock alignment hard in turns, you'll see the outsides of the tires worn.

Because of the twin's suspension geometry. Simply put, as the car rolls in a turn, the outside wheels' suspension compresses (makes sense right?). The rear suspension was designed to gain negative camber as it compresses. So as the body rolls, the tire does not roll over as much as the car's body roll, maximizing the tire's contact patch. The front suspension is different, it does not gain significant negative camber as it compresses (during body roll in a corner), and therefore allows the tire to roll over to the outside edge, minimizing traction. This is why you must give the front end more negative camber to begin with. (Another very popular BRZ trick is to run a stiff front sway bar, to limit the front body roll and maximize tire contact).

now toe..Toe-in will stabilize the car, making it track straight and not want to change direction. Toe out does the opposite, makes it twitchy, and want to change direction quickly. A car is more responsive with toe out, but significantly less stable. Just a basic definition.

FRONT Of CAR - Toe-out in the front lets the car turn in nicely, but may "tramline" down the road (finding grooves and irregularities and following them). Toe-in front makes the car hard to turn and want to "push" or understeer. I suggest going with total toe out front of -0.1 (so about -.05 per side)

REAR OF CAR - Toe-out in the rear is pretty dangerous for RWD cars, makes the car want to spin, especially under hard braking. Toe-in rear will keep the rear stable, and (here is the key) allow for you to put power down as early and as hard as possible without wheel spin. More is not always better, racers will always adjust these settings till they get it just right. For the street, the suggested settings will let you set-it-and-forget-it. Negative camber does not kill tires. Negative camber plus excessive toe (in or out) causes inner tire wear. Toe (in or out) in effect forces the car to "drag" the tire down the road, where 0 toe lets the tire roll down the road. Make sense? Negative camber will cause the tire to roll on the inside of the tire, but negative camber plus excessive toe will drag the inside of the tire down the road causing bad inner tire wear.



Pre-alignment photos (notice rear camber is jacked as it settled A LOT:











And these are just random photos of my car through various stages of wheels/tires/suspensions for peoples reference.

[IMG]https://c4.staticflickr.com/8/7687/17801142362_0***aa4638_b.jpg[/IMG]















keep em' dusty:




never rubbed. not even on track.





















cheers,

-Ivan

[Draco-REX]

This is pretty much exactly the size/wheel/offset I'm looking at upgrading to when the SC goes on..

Are coilovers required for clearance up front?

[Jive Turkey]

Originally Posted by Draco-REX

This is pretty much exactly the size/wheel/offset I'm looking at upgrading to when the SC goes on..

Are coilovers required for clearance up front?

this is a question i cannot answer as i went right to coilovers. @King Tut might be of better help here.

[King Tut]

Originally Posted by Draco-REX

This is pretty much exactly the size/wheel/offset I'm looking at upgrading to when the SC goes on..

Are coilovers required for clearance up front?

Here is the clearance of a 18x9.5 +40 wheel:







Remember that the spring perch and the wheel are in fixed positions that move together so as long as your tire is not any wider than the edge of the rim you should be fine. The problem is that while the suspension and wheel are pretty rigid, a tire is not. I don't think I would want my tire that close to the spring perch. Your options are get coilovers which give you a ton of extra space or go with a 5 mm spacer in the front. The closest thing you need to worry about rubbing on the inside is the parking brake securing bracket on the rear control arm, but that can easily be bent for more clearance.

[King Tut]

In to join the 18x9.5 +40 & 265/35/18 Club

My setup:

Advan RG-D 18x9.5 +40 Gold
Michelin Pilot Super Sport 265/35/18
BC Racing BR Type Coilovers
Cusco Rear Camber Adjustable Lower Control Arms

Alignment:

Front Camber: -2 degrees
Front Toe: Zero
Rear Camber: -1.5 degrees
Rear Toe: A little toe in

Modifications:

As Jive mentioned I trimmed the area where the rear bumper meets the rear fender. I also had my rear fenders rolled just in case. I have not done any modifications to the front fenders, but I rub the area near the reflector with lots of steering angle and any kind of compression such as pulling a hard U turn or pulling into parking spots in a parking lot. This is not a situation you should be encountering when doing any spirited driving such as a track day though. I will probably have my buddy roll that area as well next time he comes over.

Pics:

[CSG Mike]

Does this count? 255

[Cjymiller]

Subbed for meaty 18x8

[Draco-REX]

Originally Posted by King Tut

Remember that the spring perch and the wheel are in fixed positions that move together so as long as your tire is not any wider than the edge of the rim you should be fine. The problem is that while the suspension and wheel are pretty rigid, a tire is not. I don't think I would want my tire that close to the spring perch. Your options are get coilovers which give you a ton of extra space or go with a 5 mm spacer in the front. The closest thing you need to worry about rubbing on the inside is the parking brake securing bracket on the rear control arm, but that can easily be bent for more clearance.

Thanks. I'm looking at the Enkei NT03+M in 18x9.5+40, but I'm hearing they may have big-brake clearance issues. I'm normally not a fan of the RG-D style, but with the lip they look much better...

[yohan04]

Haven't took any new pictures but here's some old pictures from last winter-spring.

Enkei RPF1 18 x 9.5, +35
255-35/265-35 Federal RS-R

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[loogs]

you guys make my 17x9 245/40/17 setup look like childs play

hope to be running 18x9.5 +40 & 265/35/18 next summer. love it

[King Tut]

Originally Posted by Draco-REX

Thanks. I'm looking at the Enkei NT03+M in 18x9.5+40, but I'm hearing they may have big-brake clearance issues. I'm normally not a fan of the RG-D style, but with the lip they look much better...

RG-D is meant for brake clearance. I couldn't belive how much clearance I have now:

[Mr.]

meaty > slammed (SUBBBBEDDD)

[King Tut]

So I need to update my entry. I pulled my wheels off yesterday to install my RAYS lugs and Advan center caps. I am actually rubbing the front frame rail on both sides both in front of the wheel and behind the wheel. I am also rubbing the fender liner behind the wheel on the driver side. None of it is very bad, and I am not worried about it as I just try not to go anywhere close to full steering lock now.

[swift996]

ESM 004s Wheels (18x8/18x9)
Dunlop Direzza Z2 (235/40/18 & 255/35/18)





Note - This was prior to alignement so camber was +.2 up front and is now -1.8: